Fix the issue that client id is not saved when upgrading the offline metadata store

components/offline_pages/offline_page_metadata_store_impl.h

Index: components/offline_pages/offline_page_metadata_store_impl.h
diff --git a/components/offline_pages/offline_page_metadata_store_impl.h b/components/offline_pages/offline_page_metadata_store_impl.h
index 58ee92fde5b2f6ad24455e286c4566949b920ede..ebfda7b1214dff261e4db0f4100cee80608a700d 100644
--- a/components/offline_pages/offline_page_metadata_store_impl.h
+++ b/components/offline_pages/offline_page_metadata_store_impl.h
@@ -47,6 +47,8 @@ class OfflinePageMetadataStoreImpl : public OfflinePageMetadataStore {
   void Reset(const ResetCallback& callback) override;
 
  private:
+  friend class OfflinePageMetadataStoreImplTest;
+
   void LoadContinuation(const LoadCallback& callback, bool success);
   void LoadDone(const LoadCallback& callback,
                 bool success,
@@ -81,11 +83,6 @@ class OfflinePageMetadataStoreImpl : public OfflinePageMetadataStore {
 
   base::WeakPtrFactory<OfflinePageMetadataStoreImpl> weak_ptr_factory_;
 
-  FRIEND_TEST_ALL_PREFIXES(OfflinePageMetadataStoreImplTest,
-                           LoadCorruptedStore);
-  FRIEND_TEST_ALL_PREFIXES(OfflinePageMetadataStoreImplTest,
-                           LoadTotallyCorruptedStore);
-
   DISALLOW_COPY_AND_ASSIGN(OfflinePageMetadataStoreImpl);
 };